Here is the token pool resolution mechanism, that I've created for my home version of Shadowrun. This isn't the full system (I doubt many people here would be interested in it) just the base resolution mechanism.

Base concepts

- This system uses tokens. They have to be two-sided tokens with one side having a number and one of two distinctive color/type.
Playing cards or mahjong tiles can be used.

- Characters are mostly defined by their skills. Skills have a rating, from -1 to 6, with -1 being "incompetent", 0 being "default", 5 being "master" and 6 being "augmented master"

- Tasks have a difficulty rating from -1 to 8 as well, with -1 being "trivial" and 8 being "impossible". Tasks of difficulty 8 are always impossible.

- Each of the character's skill is linked to a pool. For example, in Shadowrun the pools will be physical, mental, technical, combat, social, spellcasting, summoning, etc. The pools are calculated from Attributes (and/or other parameters such as gear depending on the pool). The pool represents the character's ability to push himself a bit further. For the Physical pool it will represent his overall shape and stamina, for the combat pool it will represent his situational awareness, the spellcasting pool will be the synchronization of the character with the local mana, etc.

- Player get tokens for each of their pools. For rarely used pools, they can just write down somewhere the number of tokens they have and use a shared pile of tokens. For commonly used pools (such as combat pool in combat) it's better to have a distinct pool of tokens.

- Pools are recharged according to some conditions. Depending on how deterministic you want the system to be, you can decide to add some randomness to the recharging.
For example, in my rules you get half of your Physical pool when you get a good night's sleep and a meal, and you roll for the rest (using SR4 dice roll mechanism) when you can get a few minutes rest.

- Character can have some "luck/fate/edge/etc." points that let them push a bit further.

Rolls

- Success rolls are handled by comparing the skill rating with the task's difficulty rating. If the difficulty rating is below the skill rating, the action is an automatic success. If it's equals, the player needs to spend one token from the corresponding pool. If it's one point above, the player needs to spend two tokens. The player can't spend more than two tokens on an action.

- If the character can take his time, the difficulty of the task is reduced by one.

- In some cases, the character can reduce the task difficulty by one by botching the job. For example, a character can reduce the difficulty of a driving test by accepting to take some damage, or reduce the difficulty of a lock-picking test by not trying to be discreet.

- Also, in some cases, the character can get an additional token by taking a risk. For example, a character trying to jump from one roof to another can take the risk of falling down in exchange for a token. In that case, the type of the token is taken into account: one type is considered success and the other failure. If it's a success, the token is valid, if it's a failure the token is not valid and the action fails with extra bad consequences. For example, when trying to jump from roof to roof a normal failure means the character stops before jumping, realizing he won't make it. A failure after taking a risk means the character jumps and falls down.

- Luck/Fate/Edge points can be used to get additional tokens on an action

- Opposed tests: The score of each character is equal to their skill's rating + 1 for each token they spend. The character with the highest score wins, a tie means a tie, unless it's not possible in that situation in which case the defender wins. The number of token characters can spend on opposed tests can either be limited to 2 as for the success test or limited to the skill's rating, if you want a system where a less skilled character can get the advantage on a more skilled character by tiring him out.

- Extended test: The test is given a difficulty, a base time and sometimes a "minimal time". Each point above the difficulty either gives better result or divides the base time by two (with the limit of the minimal time), depending on the player's choice.

- Group tests: When multiple characters are trying to do the same thing at the same time, and when this makes it more likely for them to succeed, group tests can be used. The character with the highest skill does the action, but each additional character can give one of his token. The total number of additional token is limited by a rating such as the leadership skill of the leader of the group, or a "professional rating" or "threat rating".

To make it easier to handle big groups, a group can share a single pool, with each token in this pool considered as being worth multiple tokens (depending on the "threat rating" of the group).

- Random number: When a random number is needed (such as to handle random damages for attacks), the value of a token can be used. If a token has been spent for this action, the value of that token can be used. Otherwise, the player can take a token from his shared token pile.

- Knowledge skills: Knowledge skills don't work the same way. Characters can't spend tokens, but can spend time to research a subject and get up to two additional points. The time needed to get them depends on the subject and the means to research it.

Design notes

At the beginning, my aim was to come up with a resolution mechanism that wouldn't get in the way of the game the way dice pool rolls do (compute the size of the pool, pick up that many dice, roll them, read the results).
I liked the idea of just having a pile of tokens/deck of cards you can spend, it's faster to resolve, you just discard some tokens from a pile.

The system is very deterministic, but that's something I like quite well. In Shadowrun, you often play a professional. When things are below your level, you're expected to succeed without pulling a sweat. When things are way above your league, unless you've got some hidden resource like magic/cyber/gear/edge you're screwed. And then there's the sweet spots were things are actually challenging. This is the only case where it's actually interesting to have rolls.

Besides, in Shadowrun you often plan a mission, and then do things according to plans until the shit hits the fan. Such a mechanism, with exhausting pools, is perfect to simulate this.

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Sadly, I haven't had time to playtest this in a real game for now, so I don't know how it actually works (or doesn't) in actual play.